Idiopathic granulomatous orchitis: morphology and evaluation of its relationship to IgG4 related disease.

Abstract

Idiopathic granulomatous orchitis (IGO) is rare, thought to result from an autoimmune reaction to spermatogenic elements. Its relationship to IgG4-related disease (IgG4-RD) has not been evaluated. Sixteen orchiectomy specimens (1984-2012) with a prominent intratubular granulomatous reaction were reviewed: IGO (n = 6); intratubular germ cell neoplasia unclassified (IGCNU) with a granulomatous reaction and associated seminoma (GS, n = 6); and unclassified intratubular granulomatous orchitis not fitting into a specific entity (UGO, n = 4). Men with IGO were 32 to 86 years old, presenting with a mass suspicious for malignancy. Only one patient had a history of an inflammatory disease. Clinical follow-up was available for 2 patients with IGO, and both had no evidence of systemic IgG4-RD. All IGO cases had an epithelioid granulomatous reaction confined to seminiferous tubules, an extensive interstitial lymphoplasmacytic inflammation, 3 of 6 had prominent interstitial fibrosis, and 3 of 6 cases had plasma cells with an IgG4+/IgG+ ratio >40%. In GS, 10% to 100% of tubules with IGCNU had a granulomatous reaction, which in 3 cases replaced IGCNU cells. In contrast to IGO, GS had more intratubular multinucleated giant cells, more peritubular sclerosis, fewer interstitial plasma cells, and no interstitial fibrosis. Of the 4 UGO cases, most had predominantly interstitial with less intratubular granulomatous inflammation. Only 1 non-IGO case had elevated tissue IgG4 (GS case). It is critical and sometimes difficult to distinguish GS from IGO. IGO shares some features with IgG4-RD, yet current evidence does not support its classification as a localized manifestation of IgG4-RD occurring in the testis.

• Authors: Sarah Karram, Chia-Sui Kao, Adeboye O Osunkoya, Thomas M Ulbright, Jonathan I Epstein
• Journal: Human pathology (Hum Pathol) Vol. 45 Issue 4 Pg. 844-50 (Apr 2014) ISSN: 1532-8392 [Electronic] United States
• PMID: 24656095 (Publication Type: Journal Article)
• Copyright: Copyright © 2014 Elsevier Inc. All rights reserved.

Chemical References

• Immunoglobulin G

Topics

• Adult
• Aged
• Aged, 80 and over
• Autoimmune Diseases (immunology, pathology)
• Humans
• Immunoglobulin G (immunology)
• Immunohistochemistry
• Male
• Middle Aged
• Orchitis (immunology, pathology)